CRM Email Router & Email Configuration

Hi All,

I have some question related email router & email configuration in MS CRM 2015. I test using gmail account for both CRM email and contact email (different gmail account).

1. I try send from my gmail to CRM directly, the result is the email not received in CRM. but if I try from CRM to my gmail using email activities first, after email received in my gmail inbox and reply back the email, I have received new email activities in CRM. my question is why the email not received if I try to send directly?

2. what is email server profile use for? is there any article/link is easy to understand?

thanks.